Particular fuel injection systems employ an air-assist system to encourage atomization of fuel that is metered out of a fuel injector into the air intake stream within an air induction device. In order to employ an air-assist system, the fuel injector needs to form operative seals with a plurality of structural members. In particular, the fuel injector needs to form at least one fuel seal and at least one atmosphere seal. The fuel seal being located between the fuel rail and the fuel injector. The atmosphere seal being located between the sub-atmospheric air in an air-assist passage of the air-assist system and the atmosphere air external to the air induction device.
A known manner of forming the atmosphere seal is to provide a face seal on the portion of the fuel injector installed in an aperture in the air induction device. The face seal engages and mates with a surface within the aperture to form the required atmosphere seal when an axial load is applied to the fuel injector. To apply the axial load, fuel pressure is applied to the fuel injector, which axial moves the fuel injector. In order to achieve this axial movement, fuel injectors in known systems are positioned proximate the fuel rail without being secured to the fuel rail.